I ran them a long time ago when I was trying to make aggro work, in a format being consumed by ramp. They were an early, crude, and brutish tool to try to force aggro into relevence, at a point where I would have been happy with them as fun police, rather than a dynamic or interesting archetype.
The prison cards ended up being universally best in artifact or green ramp decks, backfiring completly, and strangling aggro even more. This was due to ramp being the deck that could most efficiently break symmetry on them. Worse, when the mana tax cards did come down, they just created dull gamestates, where people couldn't do fun things (unless you were ramp!). Sometimes bad drafters would pick them, and run them in completly inapproriate decks out of ignorance, ruining their own game experience, and those of their opponents, in the process.
Miserable, miserable, miserable cards.